Immature and mature cortical neurons engage different apoptotic mechanisms involving caspase-3 and the mitogen-activated protein kinase pathway
Immature and mature cortical neurons engage different apoptotic mechanisms involving caspase-3 and the mitogen-activated protein kinase pathway
复制标题
DOI：
10.1097/00004647-200208000-00005
复制
发表时间：
2002-08-01
影响因子：
6.3
通讯作者：
Martin, LJ
中科院分区：
文献类型：
--
作者：
Lesuisse, C;Martin, LJ
作者利用培养的小鼠皮质神经元，研究DNA损伤诱导的未成熟和成熟神经元凋亡的机制。神经元在体外存活60天（DIV60）。谷氨酸受体、突触蛋白和糖酵解酶水平的升高被用来跟踪成熟。神经元暴露于dna损伤剂喜树碱诱导未成熟（DIV5）和成熟（DIV25-30）神经元凋亡。核小体间DNA片段在成熟神经元中比在未成熟神经元中出现得更快。免疫印迹显示，在凋亡的DIV5神经元中，cleaved - caspase-3升高，而在DIV30神经元中则无升高。但免疫定位显示在DIV5和DIV30神经元中有cleaved caspase-3的积累。可逆caspase-3抑制剂可阻断DIV5神经元的凋亡，但对DIV30神经元无抑制作用。细胞外信号调节激酶/丝裂原活化蛋白激酶（Erk/MAP激酶）-42/44的磷酸化在成熟而非未成熟的神经元中发生凋亡前，而Erk54核易位和MAP激酶激酶激酶激酶1裂解为推测的caspase-3产生的促凋亡片段发生在DIV5而非DIV30神经元中。MAP激酶抑制剂抑制Erk活化可阻断两个年龄的细胞凋亡。结果表明，未成熟和成熟皮质神经元在凋亡过程中参与MAP激酶和caspase通路的不同信号机制。神经元年龄影响细胞凋亡的机制和进程。
The authors used cultured mouse cortical neurons to study mechanisms of DNA damage-induced apoptosis in immature and mature neurons. Neurons were maintained viably for 60 days in vitro (DIV60). The increased levels of glutamate receptors, synaptic proteins, and glycolytic enzyme were used to track maturation. Exposure of neurons to the DNA-damaging agent camptothecin induced apoptosis in immature (DIV5) and mature (DIV25-30) neurons. Internucleosomal fragmentation of DNA emerged more rapidly in mature neurons than in immature neurons. Immunoblotting revealed that cleaved caspase-3 increased in apoptotic DIV5 neurons but not in DIV30 neurons. but immunolocalization showed accumulation of cleaved caspase-3 in DIV5 and DIV30 neurons. A reversible caspase-3 inhibitor blocked apoptosis in DIV5 neurons but not in DIV30 neurons. Phosphorylation of extracellular signal-regulated kinase/mitogen-activated protein kinase (Erk/MAP kinase)-42/44 occurred preapoptotically in mature but not immature neurons, while Erk54 nuclear translocation and MAP kinase kinase kinase-1 cleavage into putative caspase-3-generated proapoptotic fragments occurred in DIV5 but not DIV30 neurons. Inhibition of Erk activation with MAP kinase kinase inhibitor blocked apoptosis at both ages. The results show that immature and mature cortical neurons engage different signaling mechanisms in MAP kinase and caspase pathways during apoptosis: thus. neuron age influences the mechanisms and progression of apoptosis.